The present invention relates to slot machines of the type having a plurality of reels which are rotated at relatively low speed in a bonus game.
There are widely known many kinds of slot machines, one of which is provided with three to five rotatable reels arranged in side-by-side relationship. These reels are individually brought to a stop by pushing stop button switches associated with the respective reels. On the outer peripheral surface of each of the respective reels is printed or otherwise provided an annular series of spaced symbols such as a lemon, a cherry, a figure seven or the like; and three symbols on the respective reels in stopped position are shown in windows associated one with each reel. When any one of predetermined prize-winning combinations of symbols occurs on prize-winning lines, for instance three transverse lines and two diagonal lines, i.e., five lines in total, in the case of three reels, the slot machine causes the pay out of different numbers of coins or tokens (hereinafter, these are generically called tokens) as prizes in accordance with the combinations of symbols. The number of prize-winning lines available is one, for instance the central transverse line, if only one token has been inserted and is increased in proportion to the number of tokens inserted. Thus the probability of winning prizes depends on the number of tokens inserted.
There are conventionally provided several kinds of slot machines having various distinctive features, for example slot machines wherein all of the tokens therein are paid out when a combination of figures of seven (7) on the respective reels in stopped position occur in a prize-winning line; slot machines wherein tokens are paid out in proportion to the number of tokens inserted, and slot machines wherein a fixed number of tokens are paid out when a predetermined prize-winning symbol on any one of the reels in stopped position occurs in a prize-winning line as well as when there occurs a predetermined prize-winning combination of symbols in a bonus game which is given to players upon a specified prize-winning combination of symbols occurring in the preceding game. Although a slot machine having the function of a bonus game mentioned above is intended to provide increased chances of winning prizes for players, it is still difficult to win prizes because of the reels rotating at high speed.